Wet barrel fire hydrant flow preventer

ABSTRACT

The present invention provides a fluid flow prevention apparatus for a wet barrel fire hydrant which is simple and inexpensive to install and effectively cuts off water flow while reducing water hammer. The fluid flow apparatus includes an in-line or non-hinged valve member for closing a flow passageway connected to the hydrant that is operably movable from an open to closed position upon damage to the hydrant. An adjustable damping member controls the rate of closing of the valve member to reduce the effects of water hammer.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/545,140, filed 10 Oct. 2006, which is a continuation-in-part of U.S.patent application Ser. No. 10/741,886, filed 19 Dec. 2003 (now U.S.Pat. No. 7,128,083), which claims the benefit of U.S. Provisional PatentApplication Ser. No. 60/435,433, filed 20 Dec. 2002, the entire contentsand substance of which are all incorporated herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a flow prevention apparatusfor damaged fire hydrants, and more particularly, to an adjustable flowprevention apparatus for a wet barrel fire hydrant where damage to thewater system elements is avoided while shut off of water flow from adamaged hydrant is simultaneously achieved.

2. Description of the Related Art

There are two basic types of fire hydrants manufactured today. These twotypes are commonly referred to in the trade as the “wet” barrel or“California” fire hydrant and the dry barrel fire hydrant. As the nameimplies, wet barrel fire hydrants are always supplied with water underpressure from a municipal, or other supply, water system. As such, it isthe practice to install this type of fire hydrant only in milderclimates where there is no chance of freezing. Because wet hydrants areconstantly supplied with water, however, damage to the hydrant canresult in a considerable loss of water before the damaged hydrant isdiscovered and repaired.

Where the climate is dry, or where drought conditions prevail for anylength of time, manufacturers of wet hydrants have endeavored to provideflow cut off devices to prevent loss of water in the event of damage tothe barrel, such as may result from a vehicle collision. Unfortunately,the probability of such events occurring is quite high due to thestandard location of hydrants adjacent the street curbs to facilitaterapid access by fire department personnel in the event of a fireemergency. Therefore, in the construction of wet barrel hydrants,manufacturers have proposed the use of cut off valves that are actuatedin response to a pressure drop which will occur when, for example, thebarrel is broken off from the supply pipe. In other arrangements, avalve is actuated by a mechanical linkage between the barrel and the cutoff valve so that when the barrel is removed, such as by a vehicularcollision or similar event, the valve will be quickly shut to preventany significant water loss.

With these and other devices, however, damage to the pipes and valves inthe system can occur as a result of the high pressure that theseelements experience due to the sudden closing of a supply pipe when thecut off valve is actuated as a result of the abrupt change in flowvelocity of the water. Such an abrupt change produces what is commonlyreferred to as water hammer. Water hammer refers to the pressurefluctuations associated with the change between the kinetic energy ofmoving water and pressure energy, which may be either positive ornegative. When the water in the pipe is stopped abruptly, considerableforce is exerted on the valve and oscillating shock waves are reflectedback into the municipal water system. The tremendous forces associatedwith water hammer can destroy the valve and damage other seals and pipesthroughout the water system.

Accordingly, systems have been developed to reduce the effects of waterhammer. In some systems, it has been proposed to provide an upstream cutoff valve that can be actuated gradually or even manually to preventsuch water hammer damage. These arrangements, however, can result insubstantial down stream water loss through the broken hydrant which isclearly undesirable in areas suffering drought and may also require cutoff of flow to undamaged hydrants as well.

In other arrangements, water cut off devices have been proposed whichare warranted to cut off flow to a damaged hydrant but such devices areoften difficult and expensive to install particularly in older,established water systems. For example, U.S. Pat. Nos. 4,127,142 and4,596,263 both disclose wet barrel systems that utilize a dash-potassembly connected to a “swing check” or flapper type valve. The valveis biased toward the closed position by a spring and is held open andout of the flow passageway by a holding bar connected to the upperbarrel of the hydrant. If the hydrant is sheared from its support, theholding bar releases the flapper valve and the spring urges the valveinto the flow passageway. The valve then closes due to the resultingchange in water pressure, while the dash-pot assembly prevents rapidclosure of the valve.

Although the systems disclosed by U.S. Pat. Nos. 4,127,142 and 4,596,263reduce the effects of water hammer, they still have limitations. Forexample, if the hydrant is merely damaged, rather than completelysheared off, the holding bar may actually prevent the valve fromclosing. In addition, the above systems require an underground barrelwith a lateral chamber to accommodate the arrangement of the dash-potassembly. Such an arrangement makes the use of the disclosed systemsmore difficult and expensive to install with existing water systemsand/or with systems of different sizes or types. Finally, once thedash-pot assembly is installed, the restrictive rate of closure of theflapper valve cannot be adjusted.

What is needed then, is an adjustable cut off valve for a wet barrelhydrant which is simple to install and relatively inexpensive, and thatwill effectively cut off water flow without causing water hammer in theaccompanying system. It is to such a device that the present inventionis primarily directed.

SUMMARY OF THE INVENTION

The present invention provides a fluid flow prevention apparatus for awet barrel fire hydrant which is simple to install and relativelyinexpensive, yet will effectively cut off water flow without causingwater hammering of the system's elements. The fluid flow preventionapparatus includes a valve member for closing the flow passageway of apipe connected to a wet barrel fire hydrant. The valve member ispositioned in-line with the flow passageway of the pipe and is operablymovable from an open to closed position upon damage to the hydrant. Anadjustable damping member controls the rate of closing of the valvemember to reduce the effects of water hammer when the valve membercloses.

The fluid flow prevention apparatus may also include a tube memberextending through the in-line valve member. One end of the tube memberis in fluid communication with the flow passageway of the pipe while theother end of the tube member is in fluid communication with the hydrantto allow reduced fluid flow through the tube member when the valvemember is closed. Accordingly, a signal stream of fluid is provided fromthe tube member for identifying the damaged hydrant.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows an elevational view, partly in section, of an embodiment ofthe device of the present invention.

FIG. 2 shows an elevational view, partly in section, of the embodimentshown in FIG. 1 with the valve in the closed position.

FIG. 3 shows an elevational view, partly in section, of an embodiment ofthe device having an adjustable damping member comprising an adjustabletubular body filled with viscous fluid.

DETAILED DESCRIPTION

Referring to the figures, wherein like numerals represent like parts,there is shown in FIG. 1, a standard wet barrel hydrant 10 which issecured, for example, by threaded bolts 11 to a plate 14 which ismounted on the upper end of an underground barrel 12. Typically, theplate 14 is attached to a break off bracket 16 which includes an inner,annular flange 17 engaging in a grove provided in an radially extendingflange 19 formed on the upper end of the underground barrel 12 as shown.With this arrangement, in the event of a collision or other forceimposed on the upper barrel or hydrant 10, the flange 17 will yield toallow the plate 14 to be released from the upper end of the undergroundbarrel 12.

Typically, the break off bracket 16 will be secured to the plate 14 bythreaded bolts inserted through the threaded apertures 21. The plate 14has an opening with an inside diameter slightly smaller in size than thediameter of the upper end of the underground barrel 12. With thisarrangement, a guide member in the form of a plate or bar 18 may besecured to the edge of the opening of underground barrel 12 as at 23.The manner of attachment may be by welding or any other suitable methodof attachment. A tube 20, which is threaded at opposite ends, extendsthrough a central aperture 13 provided in the guide member 18.

A nut 25 is threadedly engaged on the tube 20, on the upper end thereof,at a distance from the upper end of tube 20. An adjustable dampingmember 22 is provided between the nut 25 and the underside of the guidemember 18. It will be understood, of course, that the guide member 18may simply be a bar extending across the opening to the plate 14 at theupper end of the underground barrel 12, or it may take the form of anapertured plate so that flow of water to the upper barrel 10 will beunimpeded.

The lower end of the tube 20 is also threaded to cooperate with a nut 26that is located at the base of an opening 32 extending centrally throughan in-line valve member 28 of conventional construction. One suchhydrant valve is described in our U.S. Pat. No. 3,980,097 of Sep. 14,1976, the disclosure of which is incorporated herein by reference in itsentirety. The term “in-line” as used herein to describe the valve memberis defined as any valve that is non-hinged and aligned axially with thedirection of fluid flow. As is conventional, the in-line valve member 28includes a sealing disc 30 surrounding the central opening 32 formed inthe in-line valve member 28. The tube 20 extends through the opening 32to connect and be secured to the in-line valve member 28 by the nut 26.An additional attachment between the in-line valve body and the tube 20may also be provided, such as by a dowel pin as shown at 34.

The in-line valve member 28 is, as noted above, of conventionalconstruction and may include a set of a upstanding ears 36 whichcooperate with a seating ring 38 which serves to guide the in-line valve28 in its movement between open and closed positions in the valvehousing, or shoe 40. The valve housing 40 has an opening 42 which is inuse supplied with water under pressure from a municipal or other supplywater system. The outlet of the housing 40 at 44 will be closed when theseal 30 contacts under pressure the rim 46 of the seat 38 of the valvehousing 40 effectively preventing water from entering the flowpassageway of underground barrel 12. Although housing 40 is shown in ahorizontal configuration, the housing may also be vertical or of anyother suitable configuration.

As shown in FIG. 1, the in-line valve 28 is in an open position so thatthe water entering the valve housing 40 through its opening 42 will passthrough the seat 46 to fill the underground barrel 12 as well as theaboveground barrel or hydrant 10. Holding member 15 engages the tube 20to maintain the in-line valve 28 in an open position, so that the valvewill remain open for normal operation of the hydrant. Holding member 15may be attached to hydrant 10 or to plate 14 as a separate or integralmember, and has a predetermined retention force for maintaining valve 28in an open position during normal hydrant operation. In the event thatthe upper barrel or hydrant 10 is removed, such as by collision with avehicle, water would normally flow freely through the underground barrel12 to the exterior and be lost. According to the present invention,however, holding member 15 is removed along with hydrant 10 releasingthe tube 20, and water pressure acting on the lower end portion of thein-line valve 28 will move the valve 28 upward toward a closed positionbringing the sealing disc 30 into engagement with the seat 46 to cut offfluid flow from the valve housing 40 to underground barrel 12.

Because the valve member 28 is provided in-line with the flow passagewayof underground barrel 12, the flow of water around and over valve member28 is generally uniform during closing of the valve. Accordingly, thewater hammering effects associated with the closing of in-line valvemember 28 are less than those produced by the closing of conventionalhinged or flapper type valves where the water flow is non-uniform. Tofurther prevent water hammer or sudden pressure buildup upstream of thevalve housing 40, the closing of the in-line valve member 28 isrestrained by an adjustable damping member 22 disposed between theunderside of the guide member 18 and the adjustable nut 25 mounted onthe tube 20.

In the preferred embodiment, adjustable damping member 22 is a helicalspring disposed, as shown, with one end of the spring in engagement withthe underside of the guide member 18 and the other end resting on theupper side of the nut 25. Other types of damping devices such as atubular body 52 filled with a viscous fluid 54, as illustrated in FIG.3, can be disposed about the tube 20 to provide a damping action on theupward movement of the in-line valve 28 in the event that hydrant 10 isaccidentally removed. Adjustment of the damping action is advantageouslyeffected by adjusting the nut 25 to increase or decrease the resistanceto movement of the tube 20 through the opening 13 provided in the guidemember or plate 18 and consequent movement of the in-line valve member28 upwardly towards the valve seat 46. Normally, the damping device willbe under no compression in order to prolong the useful life of thedamper.

Referring now to FIG. 2, valve member 28 is shown in a closed position.Hydrant 10, and plate 14 have been removed, such as by collision with avehicle. Because holding member 15 is attached to either hydrant 10 orplate 14, tube 20 has been released and water pressure has moved in-linevalve member 28 into a closed position. Sealing disc 30 is shown inengagement with rim 46 effectively cutting off the main fluid flow tounderground barrel 12. Tube 20 allows reduced fluid flow (as shown witharrows) from housing 40 to the outside. Such an arrangement furtherreduces the effects of water hammer because a small amount of water isallowed to exit the water system through tube 20. This small stream ofwater also provides an identification stream indicating that the hydrantis damaged and repair is needed.

The designs of the different embodiments of the present invention allowexisting water systems to be easily and inexpensively fitted with theflow prevention apparatus described herein because wet barrel firehydrants with specially shaped underground barrels are not required dueto the in-line positioning of the valve and damping member. As statedabove, the damping member is also adjustable enabling additional controlover the rate of closing of the valve member by simply adjusting theamount of resistance provided by the damping member. Accordingly, thedamping member can provide effective resistance for reducing waterhammer in water systems with pipes of various sizes, shapes, anddiameters.

Numerous characteristics and advantages have been set forth in theforegoing description, together with details of structure and function.While the invention has been disclosed in its preferred form, it will beapparent to those skilled in the art that many modifications, additions,and deletions, especially in matters of shape, size, and arrangement ofparts, can be made therein without departing from the spirit and scopeof the invention and its equivalents as set forth in the followingclaims. Therefore, other modifications or embodiments as may besuggested by the teachings herein are particularly reserved especiallyas they fall within the breadth and scope of the claims here appended.

1. A fluid flow prevention apparatus for a wet barrel fire hydrant, thewet barrel fire hydrant being in communication with a pipe having aperiphery defining a flow passageway therethrough, the fluid flowprevention apparatus comprising: a non-hinged valve member for closingthe flow passageway of the pipe, the non-hinged valve member alignedaxially with the flow passageway of the pipe and operably movable froman open position to a closed position when a fire hydrant removing forceis imposed on the wet barrel fire hydrant; and an adjustable dampingmember for controlling the rate of closing of the non-hinged valvemember, the adjustable damping member in communication with thenon-hinged valve member, wherein the adjustable damping member preventssudden closure of the non-hinged valve member and reduces the effects ofwater hammer within the pipe.
 2. The fluid flow prevention apparatus ofclaim 1, further comprising: a tube member having first and second endsand a periphery defining a conduit therethrough, the tube memberextending through the non-hinged valve member with the first end of thetube member in fluid communication with the flow passageway of the pipe,wherein the tube member allows reduced fluid flow from the flowpassageway of the pipe when the non-hinged valve member is closed andprovides a signal stream of fluid from the tube member to identify thelocation of the removed wet barrel fire hydrant.
 3. The fluid flowprevention apparatus of claim 2, further comprising: a holding memberfor maintaining the non-hinged valve member in an open position duringnormal operation of the wet barrel fire hydrant; the holding memberoperably configured to release the non-hinged valve member from the openposition when the fire hydrant removing force is imposed on the wetbarrel fire hydrant.
 4. The fluid flow prevention apparatus of claim 3,further comprising a guide member for guiding the tube member intoengagement with the holding member.
 5. The fluid flow preventionapparatus of claim 3, further comprising: a guide member for guiding thetube member into engagement with the holding member, wherein the guidemember is located downstream of the non-hinged valve member and theadjustable damping member is positioned between the guide member and thenon-hinged valve member.
 6. The fluid flow prevention apparatus of claim5, wherein the guide member is an apertured plate through which the tubemember extends.
 7. The fluid flow prevention apparatus of claim 5,wherein the guide member is a bar extending across the flow passagewayof the pipe.
 8. The fluid flow prevention apparatus of claim 1, whereinthe adjustable damping member comprises an adjustable spring.
 9. Thefluid flow prevention apparatus of claim 1, wherein the adjustabledamping member comprises an adjustable tubular body filled with viscousfluid.
 10. The fluid flow prevention apparatus of claim 1, wherein thenon-hinged valve member is a pressure sensitive cut-off valve that isoperably closed by water pressure.
 11. The fluid flow preventionapparatus of claim 1, wherein the adjustable damping member is connectedto the non-hinged valve member by a tube member.
 12. A fluid flowprevention apparatus for a wet barrel fire hydrant, the wet barrel firehydrant having an underground barrel having an inlet and an outlet, thefluid flow prevention apparatus comprising: an in-line valve member forclosing the inlet of the underground barrel when a fire hydrant removingforce is imposed on the wet barrel fire hydrant, the in-line valvemember operably movable from an open position to a closed position whenthe fire hydrant removing force is imposed on the wet barrel firehydrant; a tube member having first and second ends and a peripherydefining a conduit therethrough, the tube member extending through thein-line valve member with the first end in fluid communication with theinlet of the underground barrel, and the second end in fluidcommunication with the outlet of the underground barrel allowing reducedfluid flow through the conduit when the in-line valve member is in theclosed position; a holding member for retaining the in-line valve memberin an open position during normal operation of the wet barrel firehydrant, the holding member communicating with the second end of thetube member and operably configured to release the in-line valve memberwhen the fire hydrant removing force is imposed on the wet barrel firehydrant; a guide member for guiding the tube member into engagement withthe holding member; and an adjustable damping member for controlling therate of closing of the in-line valve member, the adjustable dampingmember in communication with the in-line valve member, wherein the firehydrant removing force imposed on the wet barrel fire hydrant causes thein-line valve member to move from the open position to the closedposition while reducing the effects of water hammer, and wherein thetube member provides an identifying signal stream of fluid foridentifying the location of the removed wet barrel fire hydrant.
 13. Thefluid flow prevention apparatus of claim 12, wherein the adjustabledamping member comprises: an adjustable nut carried by the tube member,the nut positioned beneath the guide member; and a spring carried by thetube member, the spring positioned between the nut and the guide member,wherein the adjustment of the nut increases or decreases the resistanceto move the in-line valve member toward the closed position.
 14. Thefluid flow prevention apparatus of claim 12, the in-line valve memberfurther comprising a sealing disc for sealing the inlet of theunderground barrel when the in-line valve member is in the closedposition.
 15. The fluid flow prevention apparatus of claim 12, thein-line valve member further comprising: a seating ring in communicationwith the inlet of the underground barrel; and a pair of upstanding earsthat operably cooperate with the seating ring for guiding the in-linevalve member into the closed position.
 16. A kit for retrofitting a wetbarrel fire hydrant to have a fluid flow prevention apparatus, the wetbarrel fire hydrant having an upper barrel and an underground barrel,the underground barrel having an interior flow passageway for deliveringfluid from the underground barrel to the upper barrel, the kitcomprising: a non-hinged valve member positioned within the interior ofthe underground barrel and axially aligned with the flow passageway, thenon-hinged valve member being operably movable from an open position toa closed position for closing the flow passageway of the undergroundbarrel when a fire hydrant removing force is imposed on the upper barrelof the wet barrel fire hydrant; a seating member adapted forcommunicating with the interior of the underground barrel; the seatingmember adapted to receive the non-hinged valve member; a holding memberadapted for configuration with the upper barrel, the holding member formaintaining the non-hinged valve member in an open position duringnormal operation of the wet barrel fire hydrant; and an adjustabledamping member for controlling the rate of moving of the non-hingedvalve member from the open position to the closed position, theadjustable damping member in communication with the non-hinged valvemember to prevent sudden closure of the non-hinged valve member andreduce the effects of water hammer within the pipe.
 17. The kit of claim16, further comprising: a tube member having first and second ends and aperiphery defining a conduit therethrough, the tube member extendingthrough the non-hinged valve member and in fluid communication with theflow passageway of the underground barrel; the tube member adapted forallowing reduced fluid flow from the flow passageway of the undergroundbarrel when the non-hinged valve member is in the closed position andfor providing a signal stream of fluid to identify the removed wetbarrel fire hydrant.
 18. The kit of claim 17, further comprising a guidemember for guiding the tube member into engagement with the holdingmember.
 19. The kit of claim 17, wherein the adjustable damping membercomprises: a guide member for guiding the tube member into engagementwith the holding member; an adjustable nut carried by the tube member,the nut positioned beneath the guide member; and a spring carried by thetube member, the spring positioned between the nut and the guide member,wherein the adjustment of the nut increases or decreases the resistanceto move the non-hinged valve member toward the closed position.
 20. Thekit of claim 16, wherein the non-hinged valve member is a pressuresensitive cut-off valve that is operably closed by water pressure.